The present invention relates to pneumatic exercise devices. One of the advantages of employing pneumatic resistance in an exercise device is to reduce acceleration forces that occur when a user increases the speed of exercise movements. Acceleration forces make it difficult for a user to train at a consistent level of resistance unless constant speed of movement is maintained; furthermore, acceleration forces may contribute to user injuries during exercise. In theory, pneumatic exercise equipment would have no acceleration forces produced due to increasing speed of user movement, if the weight of the moving parts were zero. However, in practical application pneumatic exercise equipment has moving parts with weight that can potentially generate acceleration forces during exercise. These moving parts traditionally include a pressure opposing structure such as a piston rod assembly, a user interface such as a handle, and any additional mechanical linkage components such as a cable, that may be necessary to connect a pressure opposing structure and a user interface. Furthermore, exercise devices employing pneumatic resistance are often large and expensive, with complicated moving parts to transmit pneumatic resistance to the user.